C++程序  |  126行  |  4.9 KB

//
// Book:      OpenGL(R) ES 2.0 Programming Guide
// Authors:   Aaftab Munshi, Dan Ginsburg, Dave Shreiner
// ISBN-10:   0321502795
// ISBN-13:   9780321502797
// Publisher: Addison-Wesley Professional
// URLs:      http://safari.informit.com/9780321563835
//            http://www.opengles-book.com
//

/*
 * (c) 2009 Aaftab Munshi, Dan Ginsburg, Dave Shreiner
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

//
/// \file ESUtil.h
/// \brief A utility library for OpenGL ES.  This library provides a
///        basic common framework for the example applications in the
///        OpenGL ES 2.0 Programming Guide.
//
#ifndef ESUTIL_H
#define ESUTIL_H

///
//  Includes
//
#include <GLES2/gl2.h>
#include <EGL/egl.h>

#ifdef __cplusplus

extern "C" {
#endif

typedef struct
{
	GLfloat   m[4][4];
} ESMatrix;

//
/// \brief multiply matrix specified by result with a scaling matrix and return new matrix in result
/// \param result Specifies the input matrix.  Scaled matrix is returned in result.
/// \param sx, sy, sz Scale factors along the x, y and z axes respectively
//
void esScale(ESMatrix *result, GLfloat sx, GLfloat sy, GLfloat sz);

//
/// \brief multiply matrix specified by result with a translation matrix and return new matrix in result
/// \param result Specifies the input matrix.  Translated matrix is returned in result.
/// \param tx, ty, tz Scale factors along the x, y and z axes respectively
//
void esTranslate(ESMatrix *result, GLfloat tx, GLfloat ty, GLfloat tz);

//
/// \brief multiply matrix specified by result with a rotation matrix and return new matrix in result
/// \param result Specifies the input matrix.  Rotated matrix is returned in result.
/// \param angle Specifies the angle of rotation, in degrees.
/// \param x, y, z Specify the x, y and z coordinates of a vector, respectively
//
void esRotate(ESMatrix *result, GLfloat angle, GLfloat x, GLfloat y, GLfloat z);

//
// \brief multiply matrix specified by result with a perspective matrix and return new matrix in result
/// \param result Specifies the input matrix.  new matrix is returned in result.
/// \param left, right Coordinates for the left and right vertical clipping planes
/// \param bottom, top Coordinates for the bottom and top horizontal clipping planes
/// \param nearZ, farZ Distances to the near and far depth clipping planes.  Both distances must be positive.
//
void esFrustum(ESMatrix *result, float left, float right, float bottom, float top, float nearZ, float farZ);

//
/// \brief multiply matrix specified by result with a perspective matrix and return new matrix in result
/// \param result Specifies the input matrix.  new matrix is returned in result.
/// \param fovy Field of view y angle in degrees
/// \param aspect Aspect ratio of screen
/// \param nearZ Near plane distance
/// \param farZ Far plane distance
//
void esPerspective(ESMatrix *result, float fovy, float aspect, float nearZ, float farZ);

//
/// \brief multiply matrix specified by result with a perspective matrix and return new matrix in result
/// \param result Specifies the input matrix.  new matrix is returned in result.
/// \param left, right Coordinates for the left and right vertical clipping planes
/// \param bottom, top Coordinates for the bottom and top horizontal clipping planes
/// \param nearZ, farZ Distances to the near and far depth clipping planes.  These values are negative if plane is behind the viewer
//
void esOrtho(ESMatrix *result, float left, float right, float bottom, float top, float nearZ, float farZ);

//
/// \brief perform the following operation - result matrix = srcA matrix * srcB matrix
/// \param result Returns multiplied matrix
/// \param srcA, srcB Input matrices to be multiplied
//
void esMatrixMultiply(ESMatrix *result, ESMatrix *srcA, ESMatrix *srcB);

//
//// \brief return an indentity matrix
//// \param result returns identity matrix
//
void esMatrixLoadIdentity(ESMatrix *result);

#ifdef __cplusplus
}
#endif

#endif // ESUTIL_H